Targeting intracellular target-binding determinants with intracellular antibodies

ABSTRACT

The invention provides a method for inhibiting an intracellular target in a cell with a bispecific antibody comprising contacting the cell with a bispecific antibody having a first Fv fragment with a cell-penetrating determinant and a second Fv fragment with an intracellular target-binding determinant under suitable conditions so that the first Fv fragment causes the bispecific antibody to enter the cell and the second Fv fragment binds the intracellular target in the cell and thereby inhibiting the intracellular target.

This application is a divisional of U.S. Ser. No. 13/844,318, filed Mar.15, 2013, which claims the priority of U.S. Ser. No. 61/618,613, filedMar. 30, 2012, the contents of all of which are herein incorporated byreference in their entireties into the present patent application.

Throughout this application various publications are referenced. Thedisclosures of these publications in their entireties are herebyincorporated by reference into this application in order to more fullydescribe the state of the art to which this invention pertains.

BACKGROUND OF THE INVENTION

Current therapies are largely based on the use of small molecules totarget intracellular sites, because cells are impervious to largemolecules such as proteins. However, small molecule inhibitors are proneto have undesirable side effects as a result of binding unintendedtargets. By contrast, antibodies have excellent binding specificity, butmost do not penetrate living cells. Thus, the current use of therapeuticantibodies is limited to targeting molecules that are secreted orlocated on the cell membrane. Intracellular antibodies can be generatedby gene therapy, but the potential dangers have not justified its use.Cell-penetrating peptides (CPPs) also referred to as proteintransduction domains (PTDs) are currently used to transport proteinsinto cells (Chugh A, Eudes F, Shim Y S. Cell-penetrating peptides:Nanocarrier for macromolecule delivery in living cells. IUBMB Life, 62:183-193, 2010). However, an important limitation of these intracellulartransporters is that they may be targeted to endosomes through lipidrafts. In addition, some are highly cationic peptides that have beenshown to be toxic to normal cells (Toborek, M; Lee, Y W; Pu, H; Malecki,A; Flora, G; Garrido, R; Hennig, B; Bauer, H C; Nath, A. HIV-Tat proteininduces oxidative and inflammatory pathways in brain endothelium. J.Neurochem. 2003; 84(1), 169-179; Pu, H; Tian, J; Flora, G; Lee, Y W;Nath, A; Hennig, B; Toborek, M. HIV-1 Tat protein upregulatesinflammatory mediators and induces monocyte invasion into the brain.Mol. Cell. Neurosci. 2003). We identified a unique monoclonal anti-DNAantibody, mAb 3E10 described (Weisbart R H, et al. J Immunol 1990144(7): 2653-2658; ATCC Accession No. PTA 2439 hybridoma), whichpenetrates living cells and localizes in the nucleus without apparentharm (Zack, D. J., Stempniak, M., Wong, A. L., Taylor, C., Weisbart, R.H.: Mechanisms of cellular penetration and nuclear localization of ananti-double strand DNA autoantibody, J. Immunol., 157: 2082-2088, 1996).In contrast to CCPs, mAb 3E10 and its single-chain Fv fragment (scFv)are internalized through hENT2, an equilibrative nucleoside salvagepathway (Hansen J E, Tse C M, Chan G, Heinze E R, Nishimura R N,Weisbart R H. Intranuclear protein transduction through a nucleosidesalvage pathway, J Biol Chem. 2007 Jul. 20; 282(29):20790-3. Epub 2007May 24), hENT2 is expressed in most cells, but its expression isincreased in muscle and cancer cells. On the basis of these findings, wedeveloped the Fv fragment of 3E10 as an intracellular delivery systemfor large molecules (Weisbart, R. H., Stempniak, M., Harris, S., Zack,D. J., and Ferreri, K.: An autoantibody is modified for use as adelivery system to target the cell nucleus: Therapeutic implications. J.Autoimmun., 11: 539-546, 1998; Weisbart, R. H., Baldwin, R., Huh, B.,Zack, D. J., and Nishimura, R.: Novel protein transfection of primaryrat cortical neurons utilizing an antibody that penetrates living cells.J. Immunol., 164: 6020-6026, 2000; Weisbart, R. H., Wakelin, R., Chan,G., Miller, C. W. and Koeffler, P. H. Construction and expression of abi specific single-chain antibody that penetrates mutant p53 coloncancer cells and binds p53. International Journal of Oncology, Int. J.One. 25: 1113-1118, 2004; Weisbart, R H., Hansen, J., Chan, G.,Wakellin, R, Chang, S., Heinze, E., Miller, C. W., Koeffler, H. P.,Yang, F., Cole, G. M., Min, Y., and Nishimura, R. Antibody-mediatedtransduction of p53 into cancer cells. Int. J. One. 25: 1867-1873, 2004;Hansen J E, Sohn W., Kim C, Chang S S, Huang N C, Santos D G, Chan G,Weisbart R H, Nishimura R N, Antibody-mediated Hsp70 protein therapy.Brain Res. 2006 1088: 187-96; Hansen, J E; Fischer, L K; Chan, G; Chang,S S; Baldwin, S W; Aragon, R J; Carter, J J, Lilly, M; Nishimura, R N;Reeves, M E; Weisbart, R H. Antibody-mediated p53 protein therapyprevents liver metastasis in vivo. Cancer Res. 2007; 67(4); Heinze E,Baldwin S, Chan G, Hansen J, Song J, Clements D, Aragon R, Nishimura R,Reeves M, Weisbart R. Antibody-mediated FOXP3 protein therapy inducesapoptosis in cancer cells in vitro and inhibits metastasis in vivo. IntJ Oncol. 2009 July; 35(1): 167-73; Heinze E, Chan G, Mory R, Khavari R,Alavi A, Chung S Y, Nishimura R N, Weisbart R H.

Tumor suppressor and T-regulatory functions of Foxp3 are mediatedthrough separate signaling pathways. Oncology Letters. Published onlineMay, 2011). After localizing in the cell nucleus, 3E10 scFv is largelydegraded within 4 hours, thus minimizing potential toxicity.

The exquisite specificity of antibody-antigen interactions is ideal fortherapeutic applications, but the therapeutic use of antibodies islimited to extracellular targets because of limited access of antibodiesinto cells. We developed a method to deliver antibodies into cells asbispecific single-chain Fv fragments constructed with the Fv fragment ofa cell-penetrating monoclonal antibody, 3E10, which localizes to thenucleus. Since Mdm2 is an important cancer target, we selected ananti-Mdm2 monoclonal antibody, mAb 3G5, for intracellular transport totarget Mdm2-dependent cancer cells. 3G5 was shown previously to bindcritical residues L66, Y67, and E69 at the N-terminus of Mdm2 requiredfor binding to p53, and was, therefore, an excellent candidate to serveas a competitive inhibitor of Mdm2 (Chen J, Marechal V, and Levine, A J.Mapping of the p53 and mdm-2 Interaction Domains. Molecular and CellularBiology, 13: 4107-4114, 1993; Bottger A, Bottger V, Garcia-Echeverria C,Chene P, Hochkeppel H K, Sampson W, Ang K., Howard, S F., Picksley S M,Lane D P. Molecular characterization of the hdm2-p53 interaction. I.Mol. Biol. 269: 744-56, 2007; Elizabeth Rayburn, Ruiwen Zhang, Jie Heand Hui Wang. MDM2 and Human Malignancies: Expression, ClinicalPathology, Prognostic Markers, and Implications for Chemotherapy.Current Cancer Drug Targets, 5:27-41, 2005; Shangary S and Wang S,Small-molecule inhibitors of the MDM2-p53 protein-protein interaction toreactivate p53 function: a novel approach for cancer therapy. Annu. Rev.Pharmacol, Toxicol. 49: 223-41, 2009; Lane, D P. New insights into p53based therapy. Discovery Medicine. Published online, Aug. 18, 2011).Mdm2 is an E3 ubiquitin ligase that down-regulates p53 function, but italso has p53-independent growth-inhibitory functions.

Our invention demonstrates the feasibility of transporting antibodiesinto cells for therapeutic regulation of intracellular targets and thepossibility for enhanced or synergistic inhibition of the growth oftumor cells when multiple components of a regulatory pathway aretargeted with more than one therapeutic agent; furthermore, ourinvention provides novel reagents for treatment of tumors, cancers,diseases and disregulated processes along with a rationale for theircombined use in targeting a regulatory pathway disregulated in tumorcells, or alternatively, components of any number of pathways that mightbe disregulated within tumors, cancers, diseases or conditions.

SUMMARY OF THE INVENTION

The invention provides bispecific antibodies having Fv fragments with acell-penetrating determinant and a second Fv fragment with anintracellular target-binding determinant. In one embodiment, theintracellular target-binding determinant is an E3 ubiquitin-proteinligase, or tumor suppressor-interacting protein, such as MDM2. In oneembodiment, the intracellular target-binding determinant may target anoncoprotein such as a myc or ras oncoprotein. In another embodiment, theintracellular target-binding determinant may target DNA repair proteinssuch as a RAD52 protein, ataxia telangiectasia mutated protein (ATM),CHK2 or CHK1 proteins, BCL2 protein. Additional examples of proteinsassociated with DNA repair include but are not limited BRCA1, MDC1,53BP1, p53, ATR, and p21.

In one embodiment, the Fv fragment with the cell penetrating determinantis a 3E10 Fv. Additionally, in one embodiment the second Fv fragmentwith an intracellular target-binding determinant is a 3G5 Fv.

The 3E10 bispecific antibodies of the invention may further comprise oneor more amino acid sequence comprising Ala-Gly-Ile-His (AGIH) at theamino terminus of one or both of the Fv region.

The 3E10 bispecific antibodies of the invention may be joined orattached to localizing signals so as to direct the scFvs tointracellular compartments such as endoplasmic reticulum andmitochondria. Further, the 3E10 bispecific antibodies of the inventionmay incorporate enzyme cleavage sites to separate the scFvs once theyare transported into cells. Additionally, the 3E10 bispecific antibodiesof the invention may be joined to produce bispecific scFvs that bindpeptides attached to siRNAs as a method to use bispecific scFvs totransport siRNA into cells.

The invention provides method for regulating intracellular targets witha bispecific antibody comprising contacting a cell with a bispecificantibody having a Fv fragment with a cell-penetrating determinant and asecond Fv fragment with an intracellular target-binding determinant.

The invention provides a method for inhibiting an intracellular targetin a cell with a bispecific antibody comprising contacting the cell witha bispecific antibody having a first recombinant variable region of animmunoglobulin molecule with a cell-penetrating determinant (e.g. Fvfragment of mAb 3E10). Preferably the first recombinant variable regioncauses the bispecific antibody to enter the cell. Additionally, thebispecific antibody has a second recombinant variable region of animmunoglobulin molecule with an intracellular target-binding determinant(e.g. Fv fragment of mAb 3G5) under suitable conditions so that it bindsthe intracellular target in the cell so that the bispecific antibodyinhibits the intracellular target.

The invention provides a method for inhibiting an intracellular targetin a cell with a bispecific antibody comprising contacting the cell witha bispecific antibody having a first Fv fragment with a cell-penetratingdeterminant and a second Fv fragment with an intracellulartarget-binding determinant under suitable conditions so that the firstFv fragment causes the bispecific antibody to enter the cell and thesecond Fv fragment binds the intracellular target in the cell andthereby inhibiting the intracellular target.

The invention also provides a method for increasing p53 tumor suppressorprotein levels in a tumor or cancer cell by exposing the cancer cellwith a bispecific antibody having a first Fv fragment with acell-penetrating determinant and a second Fv fragment with anintracellular target-binding determinant, thereby increasing the levelof p53 tumor suppressor protein levels in a tumor or cancer cell.

The invention further provides a method for inhibiting the growth ofMDM2-addicted tumor or cancer cells in a subject by exposing the tumoror cancer cell to a bispecific antibody comprising a Fv fragment with acell-penetrating determinant of anti-DNA monoclonal antibody 3E10 and asecond Fv fragment with an intracellular target-binding determinant forMDM2, thereby inhibiting the growth of tumor or cancer cells in thesubject.

The invention also provides a method for regulating activity ofMDM2-interacting proteins with a bispecific antibody comprisingcontacting a cell with a bispecific antibody having a Fv fragment with acell-penetrating determinant and a second Fv fragment with a bindingdeterminant for MDM2.

The invention further provides a method for increasing therapeuticeffectiveness of treating tumor, cancer or a dis-regulated intracellularprocess comprising the use of combination therapy with a bispecificantibody comprising: (a) a Fv fragment with a cell-penetratingdeterminant and a second Fv fragment with an intracellulartarget-binding determinant, and (b) a second bispecific antibodycomprising a Fv fragment with a cell-penetrating determinant and anadditional second Fv fragment, with an intracellular target-bindingdeterminant for a second protein of the same biochemical pathway,intracellular signaling pathway, or regulatory network.

In one embodiment, the invention provides a bispecific antibodycomprising a first Fv fragment with a cell-penetrating determinant froman anti-DNA monoclonal antibody 3E10 or an antibody which competes withmonoclonal antibody 3E10 and a second Fv fragment with an intracellulartarget-binding determinant that inhibits the biological activity,biochemical activity, regulatory activity or cellular signal associatedwith the determinant or a macromolecule to which the determinant isattached.

In one embodiment, the invention provides a bispecific antibody havingthe amino acid sequence of SEQ ID NO:2.

In another embodiment, the invention provides a bispecific antibodyencoded by nucleic acid sequence, as shown in SEQ ID NO:1.

In yet another embodiment, the invention provides a bispecific antibodycomprising one or more of amino acid sequence of SEQ ID NOS:3, 5, 7, 9,11, 13, 15, 17, 19, 21, 23, 25, or 27.

In a further embodiment, the invention provides a bispecific antibodyencoded by a nucleic acid sequence, comprising nucleic acid sequence asshown in SEQ ID NO: 1 from nucleotide position 268 to 1833, or SEQ IDNOS:4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, or 26.

In one embodiment, the invention provides a second bispecific antibodyhaving the amino acid sequence of SEQ ID NO:29.

In another embodiment, the invention provides a second bispecificantibody encoded by nucleic acid sequence, as shown in SEQ ID NO:28.

In yet another embodiment, the invention provides a bispecific antibodycomprising one or more of amino acid sequence of SEQ ID NOS:3G, 5, 7, 9,11, 13, 15, 32, 34, 36, 38, 40, or 42.

In a further embodiment, the invention provides a bispecific antibodyencoded by a nucleic acid sequence, comprising nucleic acid sequence asshown in SEQ ID NO:28 from nucleotide position 268 to 1827, or SEQ IDNOS:4, 6, 8, 10, 12, 14, 31, 33, 35, 37, 39, or 41.

In additional embodiment, the invention contemplates disclosed aminoacid sequence of a bispecific antibody comprising conservative aminoacid substitution or substitutions.

In additional embodiment, the invention contemplates disclosed nucleicacid sequence for a bispecific antibody comprising silent mutation ormutations.

The invention also provides a bispecific antibody or a single chainantibody comprising one or more of gly-gly-gly-gly-serine repeat(s),human CH1 linker, and a swivel sequence.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1. The 3E10-3G5 bispecific antibody retains the MDM2-bindingactivity of 3G5 and the cell-penetrating activity of 3E10. (A) Schematicof the 3E10-3G5 bispecific antibody. (B) Purified 3E10-3G5 visualized bySDS-PAGE and GelCode Blue® staining. A single band is observed at theexpected molecular weight of ˜60 kDa. (C) Western blots of MC-7 celllysates probed with control, 3G5, or 3E10-3G5 demonstrate that both 3G5and 3E10-3G5 recognize and bind MDM2, (D) 3E10-3G5 penetrates COS-7cells and localizes to the nucleus similar to 3E10 scFv alone asevidenced by anti-myc staining.

FIG. 2. 3E10-3G5 impairs the growth of MDM2-addicted melanoma cells. (A)Dose-response effect of 3E10-3G5 on growth of UACC-257 cells. Shown ismean response±S.D. of duplicate determinations. There was no effect of3E10 or 3G5 alone. (B) Growth of human melanoma cells (SK-MEL-103,SK-MEL-147, UACC-62, UACC-257) was inhibited at day 3 by 10 μM 3E10-3G5compared to medium alone. Results are representative of 3 independentexperiments and are shown as mean±S.D. 3T3 are transformed mousefibroblasts, and BJ is a culture of normal human primary fibroblasts.(C) Light microscopy images demonstrating the differences in cellpopulation and morphology of melanoma cells 3 days after treatment with3E10-3G5 compared to control buffer, 3E10 alone, and 3G5 alone.

FIG. 3. 3E10-3G5 inhibits human melanoma xenograft growth in vivo. Nudemice were injected subcutaneously with 1×10⁶ UACC-257 cells on day 1 andthen observed (A) control group or (B) treated by i.p. administration of1.0 mg 3E10-3G5 on days 1-4. (C) Mean turn or volume±SEM after injectionof cells into control and treated mice. (D) Tumors in mice treated with3E10-3G5 exhibit increased levels of p53 and MDM2 as demonstrated byWestern blotting for p53 and MDM2 in tumors from three control and three3E10-3G5-treated mice.

FIG. 4 shows the sequence of 3E10-3G5 bispecific scFv cloned betweenEcoRI and XbaI in pPicZαA with the nucleic acid sequence provided in SEQID NO:1 and the encoded polypeptide in SEQ ID NO:2.

FIG. 5 shows the sequence of 3E10-PAb421 bispecific scFv cloned betweenEcoRI and XbaI in pPicZαA with the nucleic acid sequence provided in SEQID NO:28 and the encoded polypeptide in SEQ ID NO:29.

FIG. 6 shows line graphs of (A) 3E10-3G5 scFv dose response and (B)3E10-Pab421 scFv dose response on growth of a human colon cancer cellline (HT29), a human glioblastoma cell line (U251) and a humanastrocytoma cell line (LN-319) in vitro.

FIG. 7 shows bar graphs of (A) HT-29 cells on day 4; (B) HT-29 cells onday 7; (C) U-251 cells on day 4; and (D) LN319 cells on day 7 in whichcombined 3E10-3G5 and 3E10-PAb421 bispecific antibody treatment resultsin enhanced or synergistic inhibition on growth of human cancer cells invitro.

FIG. 8 shows photomicrographs of a synergistic cytotoxic effect of3E10-3G5 and 3E10-PAb421 bispecific antibody treatment on HT-29 cells invitro. Unlike HT-29, a human ovarian cell line, Skov-3, does not appearto be affected morphologically by the combined treatment; Skov-3 doesnot express p53 protein.

FIG. 9 shows line graphs of untreated HT-29 tumor (top) and HT-29 tumortreated with 3E10-PAb421 (bottom) in vivo in a nude mouse xenograftmodel.

Summary Table of SEQ ID NO and Description SEQ ID NO: DESCRIPTION 13E10-3G5 coding sequence with initiator and epitope tags nucleic andamino acid 2 3E10-3G5 coding sequence with initiator and epitope tagsamino acid 3 3E10-3G5 bispecific antibody with AGIH and no initiator orepitope tags amino acid 4 3E10 kappa light chain CDR1 nucleic and aminoacid 5 3E10 kappa light chain CDR1 amino acid 6 3E10 kappa light chainCDR2 nucleic and amino acid 7 3E10 kappa light chain CDR2 amino acid 83E10 kappa light chain CDR3 nucleic and amino acid 9 3E10 kappa lightchain CDR3 amino acid 10 3E10 VH chain CDR1 with D31N mutation nucleicand amino acid 11 3E10 VH chain CDR1 with D31N mutation amino acid 123E10 VH chain CDR2 nucleic and amino acid 13 3E10 VH chain CDR2 aminoacid 14 3E10 VH chain CDR3 nucleic and amino acid 15 3E10 VH chain CDR3amino acid 16 3G5 kappa light chain CDR1 nucleic and amino acid 17 3G5kappa light chain CDR1 amino acid 18 3G5 kappa light chain CDR2 nucleicand amino acid 19 3G5 kappa light chain CDR2 amino acid 20 3G5 kappalight chain CDR3 nucleic and amino acid 21 3G5 kappa light chain CDR3amino acid 22 3G5 VH chain CDR1 nucleic and amino acid 23 3G5 VH chainCDR1 amino acid 24 3G5 VH chain CDR2 nucleic and amino acid 25 3G5 VHchain CDR2 amino acid 26 3G5 VH chain CDR3 nucleic and amino acid 27 3G5VH chain CDR3 amino acid 28 3E10-PAb421 complete coding sequence withinitiator and epitope tags nucleic and amino acid 29 3E10-PAb421complete coding sequence with initiator and epitope tags amino acid 303E10-PAb421 bispecific antibody with AGIH and no initiator or epitopetag amino acid 31 PAb421 kappa light chain CDR1 nucleic and amino acid32 PAb421 kappa light chain CDR1 amino acid 33 PAb421 kappa light chainCDR2 nucleic and amino acid 34 PAb421 kappa light chain CDR2 amino acid35 PAb421 kappa light chain CDR3 nucleic and amino acid 36 PAb421 kappalight chain CDR3 amino acid 37 PAb421 VH chain CDR1 nucleic and aminoacid 38 PAb421 VH chain CDR1 amino acid 39 PAb421 VH chain CDR2 nucleicand amino acid 40 PAb421 VH chain CDR2 amino acid 41 PAb421 VH chainCDR3 nucleic and amino acid 42 PAb421 VH chain CDR3 amino acid

DETAILED DESCRIPTION OF THE INVENTION Definitions

To facilitate understanding of the invention, a number of terms aredefined below.

As used herein, a “bispecific antibody” means any immunologicallyreactive molecule which specifically recognizes and binds at least twodifferent targets at alternate times or at the same time. Theimmunologically reactive molecule may be a single polypeptide chain asfor example in bispecific antibody comprising two or more single chainFv (scFv) fragments. The immunologically reactive molecule may consistof more than one polypeptide chains such as bispecific antibodiescreated from two antibodies with differing antigen specificity heldtogether by disulfide bonds, chemical crosslinkers, or bridging agentswhich function to bring the two different antibodies together.

Typically, a “bispecific antibody” will contain the variable region of aheavy chain and a light chain or portions thereof to permit recognitionof a target as well as a second variable region of a heavy chain and alight chain or portions thereof of an antibody to permit recognition ofa second target.

The “bispecific antibody” may also include a constant region of heavyand/or light chain. However, a constant region is optional. Also, whenthe bispecific antibody includes a constant region of a heavy and/orlight chain, it may be the entire constant region or a portion thereof.

A “bispecific antibody” also includes its equivalent, in which at leastone determinant of the “bispecific antibody” is replaced with a nonimmunoglobulin sequence-related polypeptide or agent that recognizes oneor more of the targets. Such non immunoglobulin sequence-related peptideor agent could be discovered through screening of phage displaylibraries, peptide libraries, cDNA libraries or non-peptide libraries,such as cell penetrating peptides or aptamers. In addition to peptidesor aptamers, non immunoglobulin sequence-related agent could includenucleic acid, RNA or DNA, as well as carbohydrate or lipid and theirderivatives.

A “bispecific antibody” includes heteroconjugates with bindingspecificities for at least two different targets. For example aheteroconjugates includes a hybrid antibody created from linking twodifferent antibodies or antibody fragments or a hybrid of an antibody orantibody fragment linked to a lectin or lectin fragment or anotherdeterminant with an intracellular binding specificity or a cellpenetrating ability, so long as the heteroconjugates have bindingspecificities for at least two targets.

A “bispecific antibody” includes heteroconjugates in which a “bispecificantibody” is coupled to a therapeutic agent (e.g., chemotherapeuticagent or toxin) or an imaging agent (e.g., radioisotope).

A “bispecific antibody” may be produced by recombinant DNA methods inwhich coding sequences of immunoglobulin genes are manipulated toproduce the “bispecific antibody.” The coding sequences of theimmunoglobulin genes may be used in its entirety, mutated at specificsequences or codons, or used partially by truncating the codingsequences to produce the “bispecific antibody” or components thatresults in production of a “bispecific antibody.”

A “bispecific antibody” includes an intact antibody or a Fv fragment,Fab, Fab′ or F(ab′)2 fragment coupled chemically, disulphide bridges orby other means to a second determinant which specifically recognizes atleast a different target than the target recognized by the intactantibody or the Fv, Fab, Fab′ or F(ab′)2 fragment. The seconddeterminant includes an second intact antibody different from thebinding specificity of the first antibody or the Fv, Fab, Fab′ orF(ab′)2 fragment of the second antibody.

A “bispecific antibody” of the invention includes antibodies with notonly binding specificities for two targets but also include antibodieswith additional determinants, which may be derived from immunoglobulinsequences or non-immunoglubulin sequences, with specificities for othertarget(s).

A “bispecific antibody” includes recombinant variable regions of animmunoglobulin molecule. The F(ab′) from two different antibodies may belinked under oxidative condition to form disulphide bonds or may belinked by chemical coupling or through recombinant DNA methods.

A “bispecific antibody” includes chimeric antibodies, recombinantantibodies, humanized antibodies or human antibodies or theirderivatives.

A “bispecific antibody” includes antibodies of the invention in whichone or more of the complementarity determining region (CDR) of theinvention is used to screen for additional antibodies or agents that cancompete with the binding of the 3E10, 3G5 or PAb421 antibodies. Peptide,phage display, cDNA, or chemical libraries may be used for such ascreen.

As used herein, “anti-DNA monoclonal antibody 3E10” (also referred toherein as 3E10 antibody or mAb 3E10) refers to an antibody produced byATCC PTA 2439 or a functional fragment or variant thereof or an antibodyhaving the specificity of mAb 3E10. The full 3E10 antibody has beenpreviously described (Weisbart R H, et al. J Immunol. 1990 144(7):2653-2658; ATCC Accession No. PTA 2439 hybridoma).

As used herein “recombinant variable regions of immunoglobulinmolecules” refers to variable regions of Ig molecules which are producedby molecular biological means. Sequences encoding variable domain of theheavy and light chains may be isolated from T-cells, B-cells, leukemiccells, lymphoma cells, or immunoglobulin gene expressing cells, clonedinto expression vector systems, and introduced into a host ceil toproduce “recombinant variable regions of immunoglobulin molecules.”Alternatively, the sequences may be recombinantly produced or obtainedfrom genomic DNA. Recombinant antibodies produced in this mannerconsists of an antibody or antibody fragment with the antigen bindingspecificity dependent on the variable region, comprising frameworksequences and CDRs. Such recombinant antibodies may be formed from apolypeptide chain containing a variable region from a light chain and apolypeptide chain containing a variable region from a heavy chain oralternatively both the light chain and heavy chain variable regionscould be found within a polypeptide in which a linker is used to link byrecombinant DNA methods the coding sequences for the two variable chainregions, such as in the case of single chain Fv fragment (scFv).

When “recombinant variable regions of immunoglobulin molecules” areformed from two separate polypeptides, one for the light chain variableregion and other for the heavy-chain variable region, the recombinant Igmolecules may be an intact antibody as is normally produced by anorganism from which the coding sequences were isolated or it could be afragment. Antibody fragments could be produced either by recombinant DNAmethods allowing tailored antibodies not dependent on specific proteasecleavage sites or by proteolytic cleavage of the recombinant antibodiessuch as by IdeS, pepsin, or papain to produce Fab, F(ab′) or F(ab′)2fragments. The “recombinant variable regions of immunoglobulinmolecules” may include the entire constant region or a portion of theconstant region. In addition, the constant region of one antibody may bereplaced by recombinant DNA method with the constant region of adifferent antibody if desired.

“Single-chain antibodies” or “Fv” consist of an antibody light chainvariable domain or region (“V_(L)”) and heavy chain variable region(“V_(H)”) connected by a short peptide linker.

The peptide linker allows the structure to assume a conformation whichis capable of binding to antigen [Bird et al., (1988) Science 242:423and Huston et al. (1988) Proc. Natl. Acad. Sci. USA 85:5879].

As used herein, a “conservative amino acid substitution” is thereplacement of one amino acid with another of a similar type such thatthe binding specificity of the antibody is preserved. Amino acids of asimilar type can be classified into several groups in which one aminoacid within a group may be able to substitute for another member of thegroup:

(1) non-polar aliphatic amino acids, such as alanine, glycine,isoleucine, leucine and valine with alanine and glycine more related toeach other and isoleucine, leucine and valine more related to each otherbased on size;

(2) neutral polar amino acids, such as serine, cysteine, threonine,glutamine and asparagines, and to a lesser extent methionine;

(3) cyclic amino acid, such as proline;

(4) aromatic amino acids, such as phenylalanine, tyrosine, andtryptophan;

(5) basic amino acids, such as histidine, lysine and arginine;

(6) acidic amino acids, such as aspartic acid, glutamic acid, asparagineand glutamine;

(7) aspartic acid and asparagines;

(8) glutamic acid and glutamine, and

(9) alanine, glycine, serine and cysteine

Discussions of conservative amino acid substitution may be found in thepatent literature as well as in U.S. Pat. Nos. 5,264,558 and 7,700,544.

Moreover, the present invention includes nucleic acids with “silentmutation” or “silent mutations.” A silent mutation is a mutation in theDNA which does not result in a change to the amino acid sequence of aprotein or results in a change to the amino acid sequence of a proteinbut not its functionality. Degeneracy of the genetic code allowsmultiple codons to code for the same amino acid, allowing silentmutations to occur without changing the protein sequence. Such silentmutations are well-known and may be recited readily from publicallyavailable and accepted codon tables. In the case of silent mutations inwhich the amino acid sequence is changed but not the function of theprotein, such silent mutations are generally mutations in which oneamino acid of a certain chemical/physical characteristics is substitutedwith another of a similar type. Such mutations may involve conservativeamino acid substitutions and may be detected through evolutionarychanges but is best determine empirically.

Administration is preferably by methods including, but not limited to,intramuscular injection, subcutaneous injection, nasal spray and othermucosal delivery, intradermal injection with electroporation,electroincorporation, ultrasound, jet injector, and topical patches.

According to the present invention, where administration includes apharmaceutical formulation, preferably the formulation is a unit dosagecontaining a daily dose or unit, daily sub-dose or an appropriatefraction thereof, of the active ingredient.

The compositions of the invention can be administered by any parenteralroute, in the form of a pharmaceutical formulation comprising the activeingredient, optionally in the form of a non-toxic organic, or inorganic,acid, or base, addition salt, in a pharmaceutically acceptable dosageform. Depending upon the disorder and patient to be treated, as well asthe route of administration, the compositions may be administered atvarying doses.

In human therapy, compositions of the invention may be administeredalone but may generally be administered in admixture with a suitablepharmaceutical excipient diluent or carrier selected with regard to theintended route of administration and standard pharmaceutical practice.

In embodiments of the present invention in which polypeptides orpolynucleotides of the invention are administered parenterally, suchadministration can be, for example, intravenously, intra-arterially,intraperitoneally, intrathecally, intraventricularly, intrasternally,intracranially, intramuscularly or subcutaneously, or they may beadministered by infusion techniques. They are best used in the form of asterile aqueous solution which may contain other substances, forexample, enough salts or glucose to make the solution isotonic withblood. The aqueous solutions should be suitably buffered (preferably toa pH of from 3 to 9), if necessary. The preparation of suitableparenteral formulations under sterile conditions is readily accomplishedby standard pharmaceutical techniques well-known to those skilled in theart.

Formulations suitable for parenteral administration include aqueous andnon-aqueous sterile injection solutions which may contain anti-oxidants,buffers, bacteriostats and solutes which render the formulation isotonicwith the blood of the intended recipient; and aqueous and non-aqueoussterile suspensions which may include suspending agents and thickeningagents. The formulations may be presented in unit-dose or multi-dosecontainers, for example sealed ampoules and vials, and may be stored ina freeze-dried (lyophilised) condition requiring only the addition ofthe sterile liquid carrier, for example water for injections,immediately prior to use. Extemporaneous injection solutions andsuspensions may be prepared from sterile powders, granules and tabletsof the kind previously described.

Methods of the Invention

The invention provides a method for inhibiting an intracellular targetin a cell with a bispecific antibody comprising contacting the cell witha bispecific antibody having a first recombinant variable region of animmunoglobulin molecule with a cell-penetrating determinant (e.g. Fvfragment of mAb 3E10). Preferably the first recombinant variable regioncauses the bispecific antibody to enter the cell. Additionally, thebispecific antibody has a second recombinant variable region of animmunoglobulin molecule with an intracellular target-binding determinant(e.g. Fv fragment of mAb 3G5) under suitable conditions so that it bindsthe intracellular target in the cell so that the bispecific antibodyinhibits the intracellular target.

In one embodiment, the bispecific antibody is a chimeric, human orhumanized antibody. In another embodiment, the bispecific antibodycomprises a chimeric, human or humanized bispecific single-chain Fvfragment.

In one embodiment, the first recombinant variable region with acell-penetrating determinant (e.g. Fv fragment of mAb 3E10) is derivedfrom an anti-DNA antibody. The anti-DNA antibody may be a monoclonalantibody. In one embodiment, the monoclonal antibody is a mAb 3E10 or anantibody that competes with monoclonal antibody 3E10 and isinternalizing.

In another embodiment, the first recombinant variable region with acell-penetrating determinant (e.g. Fv fragment of mAb 3E10) is derivedfrom an antibody transported into a cell through a salvage pathway. Thesalvage pathway may be a nucleoside salvage pathway which may bemediated by equilibrative nucleoside transporters (ENTs) or SLC29 familyof integral membrane proteins. The equilibrative nucleoside transporter(ENT) or a member of the SLC29 family of integral membrane proteins maybe a transporter for purine and pyrimidine nucleosides and nucleobasesor a metabolite thereof. Further, the transporter for purine andpyrimidine nucleosides and nucleobases or a metabolite thereof may be ahuman equilibrative nucleoside transporter ENT2.

In yet another embodiment, the antibody transported into a cell througha salvage pathway may be a monoclonal antibody.

In one embodiment, the first Fv fragment comprises one or morecomplementarity determining regions (CDRs) of mAb 3E10, as specified inSEQ ID NOS:5, 7, 9, 11, 13, and 15.

In another embodiment, the first Fv fragment comprises a CDR with atleast 50% amino acid sequence identity or homology to SEQ ID NOS: 5, 7,9, 11, 13, or 15.

In another embodiment, the first recombinant variable region with acell-penetrating determinant (e.g. Fv fragment) comprises an anti-DNAmonoclonal antibody 3E10 idiotype or an idiotype that competes withmonoclonal antibody 3E10 and is internalizing.

In one embodiment, the bispecific antibody is a chimeric, human orhumanized antibody that competes with anti-DNA monoclonal antibody 3E10.The antibody that competes with monoclonal antibody 3E10 may be achimeric, human or humanized antibody that competes with the uptake ofanti-DNA monoclonal antibody 3E10 into a cell.

In another embodiment, the uptake of anti-DNA monoclonal antibody 3E10into a cell is through the equilibrative nucleoside transporter (ENTs)or a member of the SLC29 family of integral membrane proteins expressedby the cell. The equilibrative nucleoside transporter (ENTs) or a memberof the SLC29 family of integral membrane proteins is human ENT2.

In one embodiment, the cell with a bispecific antibody is from a mammal.Mammals may include but are not limited to mouse, rat, hamster, cat,dog, rabbit, bovine, pig, sheep, goat, horse, monkey and human.

In one embodiment, the second recombinant variable region with anintracellular target-binding determinant (e.g. Fv fragment of mAb 3G5 ormAb PAb421) is derived from an antibody directed against a cytosolic,nuclear, mitochondrial, endoplasmic reticulum, membrane, and/ororganelle macromolecule.

In another embodiment, the second recombinant variable region with anintracellular target-binding determinant (e.g. Fv fragment of mAb 3G5 ormAb PAb421) is derived from an anti-idiotypic antibody directed againstan idiotope, a set of idiotopes or an idiotype of an antibody directedagainst cytosolic, nuclear, mitochondrial, endoplasmic reticulum,membrane, and/or organelle macromolecule. The macromolecule may be aprotein, lipid, DNA, or RNA. Further, the protein, lipid, DNA, or RNAmacromolecule is modified with a carbohydrate, phosphate group,carboxylic acid group, methyl group, sulfate group, lipid, hydroxylgroup, amide group, amino acid, modified amino acid, selenium,ubiquitin, or SUMO protein, or contains a modified base or oxidizedbase, and combinations thereof.

In yet another embodiment, the macromolecule is a human proteinassociated with control of cell growth and proliferation, cell cycle,DNA repair, DNA integrity, transcription, replication, translation, orintracellular transport. Examples of protein include but are not limitedto Mdm2, BRCA1, MDC1, 53BP1, p53, ATM, ATR, CHK1, CHK2, WT1 (Dao, T. etal., Sci Transl Med, 2013, 5(176): 176ra33) or p21.

In another embodiment, the second recombinant variable region with anintracellular target-binding determinant (e.g. Fv fragment) is derivedfrom an anti-oncoprotein antibody or an anti-idiotypic antibody of ananti-oncoprotein antibody. In one embodiment, the anti-oncoproteinantibody or the anti-idiotypic antibody may be a monoclonal antibody andthe monoclonal antibody may be directed to the Mdm2 oncoprotein (e.g.mAb 3G5). In an embodiment, the monoclonal antibody is directed to theWT1 oncoprotein (e.g., mAb ESK1).

In another embodiment, the monoclonal antibody is directed to a bindingpartner of a tumor suppressor protein. In one embodiment, the bindingpartner of a tumor suppressor protein is Mdm2 oncoprotein. In anotherembodiment, the tumor suppressor protein is p53 protein.

In one embodiment, the monoclonal antibody is directed to an E3ubiquitin ligase. In another embodiment, the monoclonal antibodydisrupts the binding of an oncoprotein to a tumor suppressor protein.The binding of an oncoprotein to a tumor suppressor protein is thebinding of Mdm2 to p53, respectively.

In one embodiment, the bispecific antibody is largely degraded within 4hours.

The invention also provides a method for increasing p53 tumor suppressorprotein levels in a tumor or cancer cell by exposing the cancer cellwith a bispecific antibody having a first recombinant variable regionwith a cell-penetrating determinant (e.g. Fv fragment of mAb 3E10) and asecond recombinant variable region with an intracellular target-bindingdeterminant (e.g. Fv fragment of mAb 3G5), thereby increasing the levelof p53 tumor suppressor protein levels in a tumor or cancer cell.

In one embodiment, the tumor or cancer is a melanoma, soft tissuetumors, sarcomas, Ewing's sarcoma, leiomyosarcomas, lipomas,liposarcomas, malignant fibrous histiocytomas, malignant Schwannomas,rhabdomyosarcomas, osteosarcomas, brain tumors, central nervous systemgliomas, neuroblastoma, glioblastomas, astrocytomas, oligodendrogliomas,soft tissue sarcomas, osteosarcomas, breast cancer, cervical carcinomas,ovarian carcinomas, testicular tumors, urothelial carcinomas, esophagealcarcinomas, lung cancers, non-small cell lung carcinoma (NSCLC),nasopharyngeal carcinomas, colorectal cancer, or colon cancer.

The invention further provides a method for inhibiting the growth oftumor or cancer cells in a subject by exposing the tumor or cancer cellto a bispecific antibody of the invention.

The invention also provides a method for inhibiting the growth ofMDM2-addicted tumor or cancer cells in a subject by exposing the tumoror cancer cell to a bispecific antibody comprising a first recombinantvariable region with a cell-penetrating determinant (e.g. Fv fragment)of anti-DNA monoclonal antibody 3E10 and a second recombinant variableregion with an intracellular target-binding determinant for MDM2 (e.g.Fv fragment of mAb 3G5), thereby inhibiting the growth of tumor orcancer cells in the subject. In one embodiment, the tumor or cancer is amelanoma, colon adenocarcinoma, colorectal cancer, glioblastoma orastrocytoma.

The invention further provides a method for regulating activity ofMDM2-interacting proteins with a bispecific antibody comprisingcontacting a cell with a bispecific antibody having a Fv fragment with acell-penetrating determinant and a second Fv fragment with a bindingdeterminant for MDM2.

In accordance with the invention, the MDM2-interacting proteins maycomprise one or more of ABL1, APEX1, AR, ARF/P14, ARRB1, ARRB2, ATM,c-abl, CCNG1, CDKN2AIP, CK2, CTBP1, CTBP2, DAXX, DHFR, DNA pol. ε,DYRK2, E2F/DP1, E1A-associated protein EP300, FKBP3, ERBB4, FOXO4, GLN3,HDAC1, HIF-1α, HIV-1 Tat, HTATIP, IGF1R, L5/RNA, L11, MDM4, MTBP, Numb,p16, p53/TP53, P63, p73/TP73, p300/CBP, PCAF, PI3K/AKT, PML,PSMA3PSMD10, PSME3, PYHIN1, RB, RBI, RBBP6, RBL5, RFWD3, RNA, RP11,RPL5, RPL11, RPL26, RRM2B, RYBP, Sp1, Sumo1, TAFII250, TBGR1, TBP/TFIIE,TRIM13, TRIM28, Tsg101, UBC, UBXN6, USP2, USP7, and human homologs.

In one embodiment, the bispecific antibody comprises bispecificsingle-chain Fv fragments derived from cell-penetrating monoclonalantibody, mAb 3E10, and anti-MDM2 monoclonal antibody, mAb 3G5.

In another embodiment, the bispecific antibody is a recombinantantibody, chimeric antibody, humanized antibody, or human antibody, orderivatives thereof.

The invention further provides a method for increasing therapeuticeffectiveness of treating tumor, cancer or a dis-regulated intracellularprocess comprising the use of combination therapy with a bispecificantibody comprising: (a) a recombinant variable region with acell-penetrating determinant (e.g. Fv fragment of mAb 3E10) and a secondrecombinant variable region with an intracellular target-bindingdeterminant (e.g. Fv fragment of mAb 3G5), and (b) a second bispecificantibody comprising a recombinant variable region with acell-penetrating determinant (e.g. Fv fragment, of mAb 3E10) and anadditional second recombinant variable region with an intracellulartarget-binding determinant (e.g. Fv fragment of mAb PAb421) for a secondprotein of the same biochemical pathway, intracellular signalingpathway, or regulatory network.

In one embodiment, the Fv fragment with a cell-penetrating determinantis derived from an antibody transported into a cell through a salvagepathway or derived from an anti-DNA antibody. The second Fv fragmentwith an intracellular target-binding determinant is derived from ananti-oncoprotein antibody. Further, the additional second Fv fragment isderived from a monoclonal antibody directed to the C-terminus of p53tumor suppressor protein with ability to restore DNA-binding capabilityof the mutant p53 protein.

In one embodiment, the antibody transported into the cell through asalvage pathway or the antibody derived from an anti-DNA antibody is mAb3E10. In another embodiment, the antibody derived from ananti-oncoprotein antibody is mAb 3G5.

In another embodiment, the monoclonal antibody directed to theC-terminus of p53 tumor suppressor protein is PAb421 (EMD Milliporecatalog Number OP03).

In one embodiment, the bispecific antibody has amino acid sequence ofSEQ ID NO:2. In another embodiment, the bispecific antibody is encodedby nucleic acid sequence, as shown in SEQ ID NO: 1. In anotherembodiment, the bispecific antibody comprises one or more of amino acidsequence of SEQ ID NOS:3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, or27. In yet another embodiment, the bispecific antibody is encoded by anucleic acid sequence, comprising nucleic acid sequence as shown in SEQID NO:1 from nucleotide position 268 to 1833, or SEQ ID NOS:4, 6, 8, 10,12, 14, 16, 18, 20, 22, 24, or 26.

In one embodiment, the bispecific antibody additionally comprisesconservative amino acid substitution or substitutions.

In another embodiment, the nucleic acid sequence additionally comprisessilent mutation or mutations.

In another embodiment, the bispecific antibody is encoded by a nucleicacid sequence, comprising a nucleic acid sequence of SEQ ID NO:1, SEQ IDNO:1 from nucleotide position 268 to 1833, or SEQ ID NOS: 4, 6, 8, 10,12, 14, 16, 18, 20, 22, 24, or 26 with one or more conservative aminoacid substitution(s) and/or silent mutation(s).

In one embodiment, the second bispecific antibody has amino acidsequence of SEQ ID NO:29. In another embodiment, the second bispecificantibody is encoded by nucleic acid sequence, as shown in SEQ ID NO:28.In another embodiment, the second bispecific antibody comprises one ormore of amino acid sequence of SEQ ID NOS:30, 5, 7, 9, 11, 13, 15, 32,34, 36, 38, 40, or 42. In yet another embodiment, the second bispecificantibody is encoded by a nucleic acid sequence, comprising nucleic acidsequence as shown in SEQ ID NO:28 from nucleotide position 268 to 1827,or SEQ ID NOS:4, 6, 8, 10, 12, 14, 31, 33, 35, 37, 39, or 41.

In one embodiment, the bispecific antibody additionally comprisesconservative amino acid substitution or substitutions.

In one embodiment, the nucleic acid sequence additionally comprisessilent mutation or mutations.

In one embodiment, the bispecific antibody is encoded by a nucleic acidsequence, comprising a nucleic acid sequence of SEQ ID NO:28, SEQ IDNO:28 from nucleotide position 268 to 1827, or SEQ ID NOS:4, 6, 8, 10,12, 14, 31, 33, 35, 37, 39, or 41 with one or more conservative aminoacid substitution(s) and/or silent mutation(s).

The invention also provides a method for producing a bispecific antibodycomprising culturing the host vector system under suitable cultureconditions so as to produce the bispecific antibody in the host andrecovering the bispecific antibody so produced.

Compositions of the Invention

The invention provides a bispecific antibody comprising a firstrecombinant variable region of an immunoglobulin molecule with acell-penetrating determinant (e.g., Fv fragment) from an anti-DNAmonoclonal antibody 3E10 or a variable region of an immunoglobulin orpolypeptide which competes with monoclonal antibody 3E10. The bispecificantibody further comprises a second recombinant variable region of animmunoglobulin molecule with an intracellular target-binding determinant(e.g., Fv fragment of mAb 3G5) that inhibits the biological activity,biochemical activity, regulatory activity or cellular signal associatedwith the determinant or a macromolecule to which the determinant isattached. The determinant or macromolecule may be human.

The bispecific antibody may be a chimeric antibody, a recombinantantibody, an anti-idiotypic antibody, a humanized antibody, or anaffinity matured antibody. In other embodiments, the antibody fragmentis a single domain antibody, a diabody, an scfv, an scfv dimer, a dsfv,a (dsfv)₂, a dsFv-dsfv′, a bispecific ds diabody, a Fv, a Fab, a Fab′,or a F(ab′)₂. In other embodiments, the antibody fragment may beoperably attached to a constant region, e.g. wherein the constant regionmay be a kappa light chain, gamma-1 heavy chain, gamma-2 heavy chain,gamma-3 heavy chain or gamma-4 heavy chain.

In further embodiments of the aspects of the invention, the isolated orbispecific antibody is a monoclonal antibody.

In one embodiment, the first antibody (e.g. Fv) fragment comprises oneor more complementarity determining regions (CDRs) of mAb 3E10, asspecified in SEQ ID NOS:5, 7, 9, 11, 13, and 15.

In another embodiment, the bispecific antibody comprises a CDR with atleast 50% amino acid sequence identity or homology to SEQ ID NOS:5, 7,9, 11, 13, or 15.

In another embodiment, the first antibody (e.g. Fv) fragment with acell-penetrating determinant has monoclonal antibody 3E10 idiotype.

In yet another embodiment, the antibody that competes with themonoclonal antibody 3E10 is a chimeric, human or humanized antibody thatcompetes with the uptake of monoclonal antibody 3E10 into the cell. Inone embodiment, the uptake of monoclonal antibody 3E10 into the cell isthrough an equilibrative nucleoside transporter (ENTs) or a member ofthe SLC29 family of integral membrane proteins expressed by the cell. Inanother embodiment, the equilibrative nucleoside transporter (ENTs) or amember of the SLC29 family of integral membrane proteins is ENT2.

In one embodiment, the second antibody (e.g. Fv) fragment with anintracellular target-binding determinant is derived from ananti-idiotypic antibody directed against an idiotope, a set of idiotopesor an idiotype of an antibody directed against a human cytosolic,nuclear, mitochondrial, endoplasmic reticulum, membrane, and/ororganelle macromolecule.

In one embodiment, the second antibody (e.g. Fv) fragment with anintracellular target-binding determinant is derived from an antibodydirected against a cytosolic, nuclear, mitochondrial, endoplasmicreticulum, membrane, and/or organelle macromolecule.

In another embodiment, the macromolecule is a human protein, DNA, lipid,or RNA. The protein, lipid, DNA, or RNA macromolecule may be modifiedwith a carbohydrate, phosphate group, carboxylic acid group, methylgroup, sulfate group, lipid, hydroxyl group, amide group, amino acid,modified amino acid, selenium, ubiquitin, or SUMO protein, or contains amodified base or oxidized base, and combinations thereof.

In one embodiment, the macromolecule is a human protein associated withcontrol of cell growth and proliferation, ceil cycle, DNA repair, DNAintegrity, transcription, replication, translation, or intracellulartransport. In accordance with the invention, the protein may be Mdm2,BRCA1, MDC1, 53BP1, p53, ATM, ATR, CHK1, CHK2, WT1 (Dao, T. et al., SciTransl Med, 2013, 5(176): 176ra33) or p21.

In one embodiment, the Fv fragment with an intracellular target-bindingdeterminant is derived from an anti-oncoprotein antibody. In anotherembodiment, the anti-oncoprotein antibody is directed to the Mdm2oncoprotein. In a further embodiment, the anti-oncoprotein antibodydirected to the Mdm2 oncoprotein is a mAb 3G5. In another embodiment,the monoclonal antibody is directed to the WT1 oncoprotein. In a furtherembodiment, the monoclonal antibody directed to the WT1 oncoprotein is amAb ESK1.

In one embodiment, the anti-oncoprotein antibody is directed to abinding partner of a tumor suppressor protein. The binding partner of atumor suppressor may be Mdm2 oncoprotein. Further, the tumor suppressorprotein may be a p53 protein.

In one embodiment, the anti-oncoprotein antibody is directed to an E3ubiquitin ligase.

In another embodiment, the anti-oncoprotein antibody disrupts thebinding of an oncoprotein to a tumor suppressor protein.

The binding of an oncoprotein to a tumor suppressor protein may includethe binding of Mdm2 to p53.

In another embodiment, the bispecific antibody further comprises aconstant region. In one embodiment, the constant region is a kappa lightchain, gamma-1 heavy chain, gamma-2 heavy chain, gamma-3 heavy chain orgamma-4 heavy chain.

In another embodiment, the bispecific antibody is produced as arecombinant protein in a bacterial cell, yeast cell, Chinese hamsterovary (CHO) cell, insect cell, or transgenic animals. The yeast cell maybe Pichia pastoris, e.g., a X-33 cell. In one embodiment, therecombinant protein is secreted and post-translationally modified. Inanother embodiment, the post-translational modification comprisesglycosylation, proteolytic processing of signal sequences, disulfidebridge formation, and/or lipid addition.

In one embodiment, the bispecific antibody comprises one or more aminoacid sequence comprising Ala-Gly-Ile-His (AGIH) at the amino terminus ofone or both of the recombinant variable region of the immunoglobulinmolecule with a cell-penetrating determinant (e.g., a scFv fragment ofmAb 3E10).

In one embodiment, the bispecific antibody has amino acid sequence ofSEQ ID NO:2. In another embodiment, the bispecific antibody is encodedby nucleic acid sequence, as shown in SEQ ID NO: 1. In anotherembodiment, the bispecific antibody comprises one or more of amino acidsequence of SEQ ID NOS:3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, or27. In yet another embodiment, the bispecific antibody is encoded by anucleic acid sequence, comprising nucleic acid sequence as shown in SEQID NO:1 from nucleotide position 268 to 1833, or SEQ ID NOS:4, 6, 8, 10,12, 14, 16, 18, 20, 22, 24, or 26.

In one embodiment, the bispecific antibody additionally comprisesconservative amino acid substitution or substitutions. In anotherembodiment, the nucleic acid sequence additionally comprises silentmutation or mutations. In yet another embodiment, the bispecificantibody is encoded by a nucleic acid sequence, comprising a nucleicacid sequence of SEQ ID NO. 1. SEQ ID NO:1 from nucleotide position 268to 1833, or SEQ ID NOS: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, or 26with one or more conservative amino acid substitution(s) and/or silentmutation(s).

In one embodiment, the bispecific antibody have the amino acid sequenceof SEQ ID NO:29. In another embodiment, the bispecific antibody may beencoded by nucleic acid sequence, as shown in SEQ ID NO:28. In anotherembodiment, the bispecific antibody comprising one or more of amino acidsequence of SEQ ID NOS:30, 5, 7, 9, 11, 13, 15, 32, 34, 36, 38, 40, or42. In yet another embodiment, the bispecific antibody encoded by anucleic acid sequence, comprising nucleic acid sequence as shown in SEQID NO:28 from nucleotide position 268 to 1827, or SEQ ID NOS:4, 6, 8,10, 12, 14, 31, 33, 35, 37, 39, or 41.

In one embodiment, the bispecific antibody additionally comprisesconservative amino acid substitution or substitutions. In anotherembodiment, the nucleic acid sequence additionally comprises silentmutation or mutations. In another embodiment, the bispecific antibody isencoded by a nucleic acid sequence, comprising a nucleic acid sequenceof SEQ ID NO:28, SEQ ID NO:28 from nucleotide position 268 to 1827, orSEQ ID NOS:4, 6, 8, 10, 12, 14, 31, 33, 35, 37, 39, or 41 with one ormore conservative amino acid substitution(s) and/or silent mutation(s).

The invention further provides for a bispecific antibody or a singlechain antibody comprising one or more of gly-gly-gly-gly-serinerepeat(s), human CH1 linker, and a swivel sequence.

In one embodiment, the gly-gly-gly-gly-serine repeat(s) are threerepeats of gly-gly-gly-gly-serine. In another embodiment, the human CH1linker comprises the amino acid sequence as provided in SEQ ID NO:3 fromamino acid position 253 to 265 or conservative amino acidsubstitution(s) within the sequence as provided in SEQ ID NO:3 fromamino acid position 253 to 265. In one embodiment, the swivel sequencecomprises the amino acid sequence as provided in SEQ ID NO:3 from aminoacid position 266 to 271.

In one embodiment, the human CH1 linker is linked to the amino terminusof the swivel sequence by a peptide bond. In another embodiment, thehuman CH1 linker is covalently attached through its amino terminus tothe carboxyl end of a Fv fragment.

In one embodiment, the nucleic acid molecule encodes the bispecificantibody of the invention. In another embodiment, the nucleic acidmolecule is a DNA (e.g., cDNA) encoding the bispecific antibody of theinvention.

The invention also provides for a vector which comprises the nucleicacid molecule of the invention. The host vector system comprises avector of the invention in a suitable host cell. Examples of suitablehost cells include but are not limited to bacterial ceil and eukaryoticcell.

The invention also provides for a pharmaceutical composition fortreating a subject suffering from tumor, cancer or a dis-regulatedintracellular process comprising a bispecific antibody of the invention.

The invention further provides for a pharmaceutical composition fortreating a subject suffering from tumor, cancer or a dis-regulatedintracellular process comprising a bispecific antibody of the invention.

Examples of tumor or cancer include but are not limited to a melanoma,soft tissue tumors, sarcomas, Ewing's sarcoma, leiomyosarcomas, lipomas,liposarcomas, malignant fibrous histiocytomas, malignant Schwannomas,rhabdomyosarcomas, osteosarcomas, brain tumors, central nervous systemgliomas, neuroblastoma, glioblastomas, astrocytomas, oligodendrogliomas,soft tissue sarcomas, osteosarcomas, breast cancer, cervical carcinomas,ovarian carcinomas, testicular tumors, urothelial carcinomas, esophagealcarcinomas, lung cancers, non-small cell lung carcinoma (NSCLC),nasopharyngeal carcinomas, colorectal cancer, or colon cancer.

In another aspect, the invention contemplates a pharmaceuticalcomposition comprising the bispecific antibodies of the invention inassociation with a pharmaceutically acceptable carrier. Thepharmaceutical compositions preferably include suitable carriers andadjuvants which include any material which when combined with themolecule of the invention retains the molecule's activity and isnon-reactive with the subject's immune system. These carriers andadjuvants include, but are not limited to, ion exchangers, alumina,aluminum stearate, lecithin, serum proteins, such as human serumalbumin, buffer substances such as phosphates, glycine, sorbic acid,potassium sorbate, partial glyceride mixtures of saturated vegetablefatty acids, phosphate buffered saline solution, water, emulsions (e.g.oil/water emulsion), salts or electrolytes such as protamine sulfate,disodium hydrogen phosphate, potassium hydrogen phosphate, sodiumchloride, zinc salts, colloidal silica, magnesium trisilicate, polyvinylpyrrolidone, cellulose-based substances and polyethylene glycol. Othercarriers may also include sterile solutions; tablets, including coatedtablets and capsules. Typically such carriers contain excipients such asstarch, milk, sugar (e.g. sucrose, glucose, maltose), certain types ofclay, gelatin, stearic acid or salts thereof, magnesium or calciumstearate, talc, vegetable fats or oils, gums, glycols, or other knownexcipients. Such carriers may also include flavor and color additives orother ingredients. Compositions comprising such carriers are formulatedby well-known conventional methods. Such compositions may also beformulated within various lipid compositions, such as, for example,liposomes as well as in various polymeric compositions, such as polymermicrospheres.

In a further embodiment, the bispecific antibody is conjugated to thechemotherapeutic agent, a toxin, a radioisotope, or a detectable label.

In another embodiment, the invention provides an article of manufacturecomprising a container and a composition of the invention containedtherein.

In embodiments of the articles of manufacture of the invention, thearticle of manufacture comprises a bispecific antibody of the inventionor antigen-binding fragment thereof operably attached to achemotherapeutic agent, a toxin, a radioisotope.

In one embodiment, the compositions of the invention further comprises atherapeutic agent admixed with the bispecific antibody. The therapeuticagent may be an anti-cancer agent which may be lenalidomide, ipilimumab,rituximab, alemtuzumab, ofatumumab, flavopiridol, Adriamycin,Dactinomycin, Bleomycin, Vinblastine, Cisplatin, acivicin; aclarubicin;acodazole hydrochloride; acronine; adozelesin; aldesleukin; altretamine;ambomycin; ametantrone acetate; amino glutethimide; amsacrine;anastrozole; anthramycin; asparaginase; asperlin; azacitidine; azetepa;azotomycin; batimastat; benzodepa; bicalutamide; bisantrenehydrochloride; bizelesin; bleomycin sulfate; brequinar sodium;bropirimine; busulfan; cactinomycin; calusterone; caracemide;carbetimer; carboplatin; earubicin hydrochloride; carzelesin;cedefingol; chlorambucil; cirolemycin; cladribine; crisnatol mesylate;cyclophosphamide; cytarabine; dacarbazine; daunorubicin hydrochloride;decitabine; dexonriaplatin, dezaguanine; dezaguanine mesylate;diaziquone; doxorubicin; doxorubicin hydrochloride; droloxifene;droloxifene citrate; dromostanolone propionate; duazomycin; edatrexate;eflornithine hydrochloride; elsamitrucin; enloplatin; enpromate;epipropidine; epirubicin hydrochloride; erbulozole; esorubicinhydrochloride; estramustine; estramustine phosphate sodium; etanidazole;etoposide; etoposide phosphate; etoprine; fadrozole hydrochloride;fazarabine; fenretinide; floxuridine; fludarabine phosphate;fluorouracil; flurocitabine; fosquidone; fostriecin sodium; gemcitabine;gemcitabine hydrochloride; hydroxyurea; idarubicin hydrochloride;ifosfamide, ilmofosine; iproplatin, irinotecan hydrochloride; lanreotideacetate, letrozole; leuprolide acetate; liarozole hydrochloride;lometrexol sodium; lomustine; losoxantrone hydrochloride; masoprocol;maytansine; mechlorethamine hydrochloride; megestrol acetate;melengestrol acetate, melphalan; menogaril; mercaptopurine;methotrexate; methotrexate sodium; metoprine; meturedepa; mitindomide;mitocarcin; mitocromin; mitogillin; mitomalcin; mitomycin; mitosper;mitotane; mitoxantrone hydrochloride; mycophenolic acid; nocodazole;nogalamycin; ormaplatin; oxisuran; pegaspargase, peliomycin;pentamustine; peplomycin sulfate; perfosfamide; pipobroman; piposulfan;piroxantrone hydrochloride; plicamycin; plomestane; porfmer sodium;porfiromycin; prednimustine; procarbazine hydrochloride; puromycin;puromycin hydrochloride; pyrazofurin; riboprine; rogletimide; safingol;safingol hydrochloride; semustine; simtrazene; sparfosate sodium;sparsomycin; spirogerranium hydrochloride; spiromustine; spiroplatin;streptonigrin; streptozocin; sulofenur; talisomycin; tecogalan sodium;tegafur; teloxantrone hydrochloride; temoporfin; teniposide; teroxirone;testolactone; thiamiprine thioguanine, thiotepa; tiazofurin;tirapazamine; toremifene citrate; trestolone acetate; triciribinephosphate; trimetrexate; trimetrexate glucuronate; triptorelin;tubulozole hydrochloride, uracil mustard; uredepa; vapreotide;verteporfm; vinblastine sulfate, vincristine sulfate; vindesine;vindesine sulfate; vinepidine sulfate; vinglycinate sulfate;vinleurosine sulfate; vinorelbine tartrate; vinrosidine sulfate;vinzolidine sulfate, vorozole; zeniplatin; zinostatin; and zorubicinhydrochloride.

In another embodiment, the compositions of the invention furthercomprising a therapeutic agent admixed with the bispecific antibody andthe therapeutic agent may be an alkylating agent which includes but arenot limited to nitrogen mustards (e.g., bendamustine, mechloroethamine,cyclophosphamide, chlorambucil, melphalan), ethylenimine andmethylmelamines (e.g., hexamethiymelamine, thiotepa), alkyl sulfonates(e.g., busulfan), nitrosoureas (e.g., carmustine, lomustine, semustine,streptozocin), or triazenes (decarbazine).

Kits of the Invention

According to another aspect of the invention, kits are provided. Kitsaccording to the invention include package(s) comprising composition ofthe invention.

The phrase “package” means any vessel containing compositions presentedherein. In preferred embodiments, the package can be a box or wrapping.Packaging materials for use in packaging pharmaceutical products arewell known to those of skill in the art. Examples of pharmaceuticalpackaging materials include, but are not limited to, blister packs,bottles, tubes, inhalers, pumps, bags, vials, containers, syringes(including pre-filled syringes), bottles, and any packaging materialsuitable for a selected formulation and intended mode of administrationand treatment.

The kit can also contain items that are not contained within the packagebut are attached to the outside of the package, for example, pipettes.

Kits may optionally contain instructions for administering compositionsof the present invention to a subject having a condition in need oftreatment. Kits may also comprise instructions for approved uses ofcomponents of the composition herein by regulatory agencies, such as theUnited States Food and Drug Administration. Kits may optionally containlabeling or product inserts for the present compositions. The package(s)and/or any product insert(s) may themselves be approved by regulatoryagencies. The kits can include compositions in the solid phase or in aliquid phase (such as buffers provided) in a package. The kits also caninclude buffers for preparing solutions for conducting the methods, andpipettes for transferring liquids from one container to another.

The kit may optionally also contain one or more other compositions foruse in therapies as described herein. In certain embodiments, thepackage(s) is a container for intravenous administration.

The following examples are presented to illustrate the present inventionand to assist one of ordinary skill in making and using the same. Theexamples are not intended in any way to otherwise limit the scope of theinvention.

EXAMPLES Example 1

Materials and Methods

Cell Lines

Cell lines obtained from the American Type Culture Collection (ATCC)include: COS-7 monkey kidney cells; MC-7 human ovarian cancer cells thatover-express MDM2; 3T3 transformed mouse fibroblasts; BJ primary humanfibroblasts. Human melanoma cells sensitive to MDM2 inhibition wereobtained from Maria S. Soengas, Madrid, Spain, and included SK-MEL-103,SK-MEL-147, UACC-62, and UACC-257. These cell lines were notauthenticated by our laboratory after receiving them.

Design, Expression, and Purification of the 3E10-3G5 Bispecific Antibody

3G5 hybridoma was obtained from Arnold J. Levine, Princeton University.3G5 Vk and VH were cloned by RT-PCR from hybridoma RNA with degenerateprimers designed to identify mouse immunoglobulin variable region genes,and 3G5 scFv was constructed as described previously (4). Variableregion heavy and light chains were attached with a (GGGGS)₃ linker. TheFv fragments were connected with a linker composed of CH1 sequencescombined with a swivel sequence (6), 3E10-3G5 bispecific scFv cDNA wasconstructed in pPicZαA (Invitrogen, Carlsbad, Calif.; Catalog No.VI95-20) between the EcoRI and XbaI cloning sites in frame with theC-terminal myc-his₆ tag. Plasmids were transfected into X-33 cells, anda high-secreting clone was identified as described previously (6).Bispecific antibody was purified from X-33 supernatant by metalchelation chromatography on Ni-NTA-Agarose. The bispecific antibody wasshown to be stable at 4° C. for 3 months.

Cell Penetration Assay

COS-7 cells were incubated with control media, media containing 10 μM3E10 scFv, or media containing 10 μM 3E10-3G5 for one hour. Media wasthen removed from the cells, and cells were washed, fixed, and stainedwith an anti-myc antibody as described previously (3).

In Vitro Assays of 3E10-3G5 Cytotoxicity

Cells were grown in DMEM with 10% FCS. Adherent cells were removed withEDTA and distributed in 96-well plates overnight in the presence ofmedium alone, 3E10, or 3E10-3G5. Growth was evaluated after 3 days bycounting cells. Results were expressed as percent total cell number(relative to control)±S.D.

In Vivo Assays of 3E10-3G5 Cytotoxicity

Animal studies were done under a protocol approved by the VeteransAffairs Institutional Animal Care and Use Committee. Nude mice (nu/nu)were obtained from The Jackson Laboratory, Bar Harbor, Me. Six Nude micewere injected subcutaneously with 1×10⁶ UACC-257 cells and observed(control). Six Nude mice were injected subcutaneously with 1×10⁶UACC-257 cells on day 1 and treated with intraperitoneal injections of1.0 mg 3E10-3G5 scFv on days 1 through 4. Tumor volume (mm³) wasmeasured in mice that developed tumors, and animals were euthanized whentumors exceeded 2000 mm³ or at the termination of the experiment on day22.

Western Blot Assays

UACC-257 tumors were excised, and tumor tissue was lysed in 2% SDS,Protein (20 μg) from each tumor was electrophoresed in a 4-20%polyacrylamide gradient, gel and then transblotted to a nylon membrane.Western blots were probed with antibodies to p53, MDM2, and actin.

Statistical Analyses

Significant differences in tumor growth were determined by Students ttest.

Results

3E10-3G5 Retains the MDM2-Binding Activity of 3G5 and theCell-Penetrating Activity of 3E10

A 3E10-3G5 bispecific antibody composed of the single chain variablefragments of the cell-penetrating 3E10 antibody and the anti-MDM2 3G5antibody was produced as a secreted protein by Pichia pastoris X-33cells transfected with pPicZαA containing the bispecific scFv cDNA (FIG.1A). 3E10-3G5 was purified from yeast supernatant by metal chelationchromatography on Ni-NTA-Agarose as described previously (6) (FIG. 1B).Purified 3E10-3G5 was used as a probe for MDM2 in a Western blot, assayon lysates from MC-7 cells over-expressing MDM2, and was found torecognize and bind MDM2 similar to the full 3G5 antibody and withsimilar binding specificity (FIG. 1C). MC-7 cells were selected as aconvenient source of MDM2. Next, 3E10-3G5 was applied to COS-7 cells inculture and was observed to penetrate into the cells and localize innuclei similar to 3E10 scFv alone (FIG. 1D). COS-7 cells over-expresshENT-2 and served as a convenient model cell to demonstrate cellularpenetration by the bispecific scFv. These results demonstrate that the3E10-3G5 bispecific antibody retains the cell-penetrating activity of3E10 scFv and the MDM2-binding activity of 3G5 scFv.

3E1G-3G5 Impairs the Growth of MDM2-Addicted Melanoma Cells

We next investigated the impact of 3E10-3G5 on melanoma cells known tobe sensitive to MDM2 inhibition (10). UACC-257 melanoma cells wereincubated for 3 days with media containing concentrations of 3E10-3G5ranging from 0-10 μM. 3E10 and 3G5 alone were used as controls and hadno observable effect on the growth or morphology of UACC-257 melanomacells compared to culture medium (FIG. 2C). However, 3E10-3G5 delayedthe growth of the cells in a dose-responsive manner, with significantgrowth delay observed at a dose of 10 μM (FIG. 2A). A similar effect wasobserved in additional MDM2-addicted melanoma cell lines, with markedinhibition of growth and distinct morphological changes observed in allof the melanoma cell lines tested (FIGS. 2B and 2C). As expected, 3E10and 3G5 alone had no apparent effect on any of the melanoma cell lines(FIG. 2). Importantly, 3E10-3G5 had only a mild impact on the growth ofmurine 3T3 transformed fibroblasts and had no effect on the growth of BJprimary human fibroblasts (FIG. 2B). Taken together these data suggestthat 3E10-3G5 successfully inhibited MDM2 in vitro and caused a growthdelay specifically in the MDM2-addicted cells.

3E10-3G5 Inhibits Growth of Melanoma Tumors In Vivo

The activity of 3E10-3G5 in vivo was tested in a human melanomaxenograft model. Nude mice were injected subcutaneously with 1×10⁶UACC-257 cells, and mice were observed or treated for 4 consecutive dayswith intraperitoneal injections of 1.0 mg 3E10-3G5 beginning at day 1.Four mice in the control group and five mice in the experimental groupdeveloped tumors. Mice that developed tumors were then followed closelyand tumor volumes were measured. Importantly, treatment with 3E10-3G5was not associated with any clinical toxicity, as treated mice wereindistinguishable from control mice with respect to their appearance andactivity. However, treatment with 3E10-3G5 significantly inhibited tumorgrowth at day 20 (p=0.041) and at the termination of the experiment onday 22 (p=0.026) (FIGS. 3A-3C). In order to probe the mechanismresponsible for tumor growth inhibition, we evaluated the relativelevels of p53 and MDM2 in representative tumors from three untreatedmice and three mice treated with 3E10-3G5. Treatment with 3E10-3G5increased the expression of MDM2 and p53 as shown in Western blots oftumor lysates probed with antibodies to p53 and MDM2 (FIG. 3D). Actinserved as a loading control. These results are similar to changes inMDM2 and p53 levels observed in cells and tumors treated with smallmolecule inhibitors of MDM2 (10) and further suggest that 3E10-3G5successfully inhibited MDM2 in vivo.

Discussion

We have demonstrated that treatment with a 3E10-3G5 bispecific antibodyimpairs the growth of melanoma cells in vitro and in vivo. This growthdelay is likely the result of increased levels of activated p53 thathave been freed from inhibition by MDM2 by the action of the 3G5antibody fragment. In keeping with this hypothesis, elevated levels ofp53 were observed in tumors in mice treated with the bispecificantibody. We also noted that these tumors exhibited increased levels ofMDM2, which is consistent with results obtained by others with MDM2inhibitors such as Nutlin-3, and is likely the result of increasedlevels of p53 driving additional production of MDM2 (10). Since MDM2 hasnumerous p53-independent effects (10) it is possible that the impact of3E10-3G5 on the melanoma cells and tumors is the result of an effect ondiverse metabolic pathways in addition to its impact on p53 function.Although we administered micromolar amounts of 3E10-3G5 to mice, onlynanomolar amounts are internalized intracellularly consistent withantigen-binding specific effects.

We previously constructed and demonstrated efficacy of acell-penetrating bispecific antibody composed of 3E10 scFv and the scFvfragment of mAb PAb421, an antibody that binds and restores the functionof some p53 mutants (6). In the present study we have extended ourcell-penetrating bispecific antibody technology by demonstrating theeffectiveness of this approach in modulating MDM2 activity in vivo.Since p53 activity can be inhibited by mutation and/or over-expressionof MDM2, combination therapy with 3E10-3G5 and 3E10-PAb421 may proveparticularly useful in select tumor cells.

Our studies establish proof-of-principle for the use of thecell-penetrating antibody 3E10 as a transport vehicle to delivertherapeutic antibody fragments directed to intracellular andintranuclear targets. The exquisite antigen-binding specificity ofantibodies delivered into intracellular compartments will likely resultin improved therapeutic indices by avoiding off-target bindingresponsible for toxic side effects of small molecule inhibitors. Inaddition, cell-penetrating bispecific antibodies can be designed thatbind intracellular epitopes such as transcription factors and DNA repairproteins that cannot presently be targeted with small moleculeinhibitors and are currently considered undruggable. The use ofcell-penetrating bispecific antibodies in targeted molecular therapywill significantly broaden the spectrum of accessible intracellulartargets and may have a profound impact in cancer therapy.

Example 2

3E10-PAb421 Inhibits Growth of HT29 Cells In Vitro and In Vivo

3E10-PAb421 bispecific single-chain antibody was assayed in vitro forcytotoxicity against the colon cancer cell line, HT29 and glioblastomacell line, U251 both containing p53 mutation R273H. Also tested was theastrocytoma cell line, LN319 containing p53 mutation R175H. All of thecell lines showed dose-response inhibition of growth in response to3E10-PAb421 (FIG. 6). Moreover, 3E10-PAb421 and 3E10-3G5 weresynergistic in inhibiting the growth of cancer cells (FIG. 7).Cytotoxicity in vitro is shown in a photomicrograph (FIG. 8). Nude micewere used to study the effect of 3E10-PAb421 on the growth of HT29cancer cells in vivo. Mice were injected with 2×10⁶ HT29 cells in thehind flank. When tumors reached 400 mm³, 1.5 mg of 3E10-PAb421 wasinjected intraperitoneally daily. 3E10-PAb421 inhibited growth of tumors2 to 3 days following initiation of therapy (FIG. 9).

REFERENCES

1. Zhang J, Yang P L, Gray N S. Targeting cancer with small moleculekinase inhibitors. Nature Reviews Cancer 2009; 9: 28-39.

2. Zack D J, Stempniak M, Wong A L, Taylor C, Weisbart R H. Mechanismsof cellular penetration and nuclear localization of an anti-doublestrand DNA autoantibody. J Immunol 1996, 157: 2082-8.

3. Hansen I E, Tse C M, Chan G, Heinze E R, Nishimura R N, Weisbart R H.Intranuclear protein transduction through a nucleoside salvage pathway.J Biol Chem 2007; 282: 20790-3.

4. Weisbart R H, Stempniak, M, Harris, S, Zack, D J, Ferreri K, Anautoantibody is modified for use as a delivery system to target the cellnucleus: Therapeutic implications. J Autoimmun 1998; 11: 539-46.

5. Weisbart R H, Baldwin R, Huh B, Zack D J, Nishimura R, Novel proteintransfection of primary rat cortical neurons utilizing an antibody thatpenetrates living cells. J Immunol 2000, 164: 6020-6.

6. Weisbart R H, Wakelin R, Chan G, Miller C W, Koeffler P H.Construction and expression of a bispecific single-chain antibody thatpenetrates mutant p53 colon cancer cells and binds p53. Int J One 2004;25: 1113-8.

7. Hansen J E, Fischer L K, Chan G, Chang S S, Baldwin S W, Aragon R Jet al. Antibody-mediated p53 protein therapy prevents liver metastasisin vivo. Cancer Res 2007; 67: 1769-74.

8. Heinze E, Baldwin S, Chan G, Hansen J, Song J, Clements D et al.Antibody-mediated FOXP3 protein therapy induces apoptosis in cancercells in vitro and inhibits metastasis in vivo. Int J Oncol 2009; 35:167-73.

9. Zhan X, Ander B P, Liao I H, Hansen J E, Kim C, Clements D et al.Recombinant Fv-Hsp70 protein mediates neuroprotection after focalcerebral ischemia in rats. Stroke 2010; 3: 538-43.

10. Verhaegen M, Checinska A, Riblett M B, Wang S, Soengas M S,E2F1-dependent oncogenic addiction of melanoma cells to MDM2. Oncogene2012; 7: 828-41.

11. Chen J, Marechal V, Levine A J. Mapping of the p53 and mdm-2Interaction Domains. Mol. & Cell Biol 1993; 13: 4107-14.

12. Bottger A, Bottger V, Garcia-Echeverria C, Chene P, Hochkeppel H K,Sampson W et al. Molecular characterization of the hdm2-p53 interaction.1997; 269: 744-56.

13. Rayburn E, Zhang R, He J, Wang H. MDM2 and Human Malignancies:Expression, Clinical Pathology, Prognostic Markers, and Implications forChemotherapy. Current Cancer Drag Targets 2005; 5: 27-41.

14. Shangary S, Wang S. Small-molecule inhibitors of the MDM2-p53protein-protein interaction to reactivate p53 function: a novel approachfor cancer therapy. Annu Rev Pharmacol Toxicol 2009; 49: 223-41.

15. Lane D P, Brown C J, Verma C, Cheok C F. New insights into p53 basedtherapy. Discovery Med 2011; 63: 107-17.

What is claimed is:
 1. A method for inhibiting the growth of tumor orcancer cells associated with Mdm2, MDC1, 53BP1, ATR, CHK1, CHK2, or p21expression or activity in a subject by exposing the tumor or cancercells to a bispecific antibody having a first Fv fragment with acell-penetrating determinant of a 3E10 monoclonal antibody and a secondFv fragment with an intracellular target-binding determinant thatinhibits an intracellular target under suitable conditions so that thefirst Fv fragment causes the bispecific antibody to enter the cells andthe second Fv fragment binds the intracellular target in the cells andinhibits the intracellular target, wherein the first Fv fragmentcomprises a heavy chain variable domain comprising the followingcomplementarity determining region (CDR) amino acid sequences: a. CDRH1comprising SEQ ID NO: 11, b. CDRH2 comprising SEQ ID NO: 13 and c. CDRH3comprising SEQ ID NO: 15; and, a light chain variable domain comprisingthe following complementarity determining region (CDR) amino acidsequences: a. CDRL1 comprising SEQ ID NO: 5, b. CDRL2 comprising SEQ IDNO: 7, and c. CDRL3 comprising SEQ ID NO: 9; wherein the second Fv bindsMdm2, MDC1, 53BP1, ATR, CHK1, CHK2, or p21 protein, thereby inhibitingthe growth of tumor or cancer cells that express Mdm2, MDC1, 53BP1, ATR,CHK1, CHK2, or p21 protein in the subject.
 2. The method of claim 1,wherein the bispecific antibody has the amino acid sequence of SEQ IDNO:2 or
 3. 3. The method of claim 1, wherein the bispecific antibody isencoded by the nucleic acid sequence as shown in SEQ ID NO:1.
 4. Themethod of claim 1, wherein the bispecific antibody is chimeric, human orhumanized.
 5. The method of claim 1, wherein the second Fv fragment withan intracellular target-binding determinant is derived from ananti-oncoprotein antibody or an anti-idiotypic antibody of ananti-oncoprotein antibody.
 6. The method of claim 5, wherein theanti-oncoprotein antibody or the anti-idiotypic antibody is a monoclonalantibody.
 7. The method of claim 6, wherein the monoclonal antibodybinds the Mdm2 oncoprotein.
 8. The method of claim 7, wherein themonoclonal antibody that binds the Mdm2 oncoprotein is mAb 3G5.
 9. Themethod of claim 1, wherein the bispecific antibody comprises the secondFv fragment comprising (a) a light chain variable domain comprisingcomplementarity determining regions of 3G5 monoclonal antibody and (b) aheavy chain variable domain comprising complementarity determiningregions of 3G5 monoclonal antibody.
 10. The method of claim 9, whereinthe complementarity determining regions of the second Fv fragmentcomprising a light chain variable domain has an amino acid sequence asprovided in SEQ ID NO:17 for CDR1, SEQ ID NO:19 for CDR2 and SEQ IDNO:21 for CDR3.
 11. The method of claim 9, wherein the complementaritydetermining regions of the second Fv fragment comprising a heavy chainvariable domain has an amino acid sequence as provided in SEQ ID NO:23for CDR1, SEQ ID NO:25 for CDR2 and SEQ ID NO:27 for CDR3.
 12. Themethod of claim 9, wherein the bispecific antibody comprises the secondFv fragment comprising (a) a light chain variable domain comprisingcomplementarity determining regions of 3G5 monoclonal antibody having anamino acid sequence as provided in SEQ ID NO:17 and encoded by a nucleicacid sequence as provided in SEQ ID NO:16 or equivalent for CDR1, SEQ IDNO:19 and encoded by a nucleic acid sequence as provided in SEQ ID NO:18or equivalent for CDR2 and SEQ ID NO:21 and encoded by a nucleic acidsequence as provided in SEQ ID NO:20 or equivalent for CDR3; and (b) aheavy chain variable domain comprising complementarity determiningregions of 3E10 monoclonal antibody (ATCC Accession No. PTA 2439) havingan amino acid sequence as provided in SEQ ID NO:23 and encoded by anucleic acid sequence as provided in SEQ ID NO:22 or equivalent forCDR1, SEQ ID NO:25 and encoded by a nucleic acid sequence as provided inSEQ ID NO:24 or equivalent for CDR2 and SEQ ID NO:27 and encoded by anucleic acid sequence as provided in SEQ ID NO:26 or equivalent forCDR3, wherein equivalent refers to degeneracy of genetic code allowingmultiple codons to code for the same amino acid.
 13. The method of claim1, wherein the bispecific antibody is encoded by a nucleic acid sequencecomprising the nucleic acid sequence as shown in SEQ ID NO:1 fromnucleotide position 268 to
 1833. 14. The method of claim 4, wherein thechimeric, the human or the humanized antibody competes with anti-DNAmonoclonal antibody 3E10 for binding to DNA.